In communication, especially in wireless communication, there are many factors that have effects on the quality of the communication. Some of these factors are due to the communication channel between the transmitter and the receiver, some are due to the non-idealities occurring in the transmitter and the receiver, especially in the radio frequency and analogue parts of the apparatuses.
In wireless communication, used frequencies tend to be high and modulation methods complex. These factors present challenges in the design of communication apparatuses as the aim is to maximize the capacity of the available communication channel and the quality.
Some of the problems related to wireless communication are common phase error and carrier frequency offset. These problems are inherent especially when carrier frequencies are high.